Sæll Haukur.

> Perhaps - but keep in mind that Icelandic has both broken
> and unbroken forms of this word stem.
>
> birki
> björk
> bjarkan

Yes, indeed. Icelandic has preserved a lot of unbroken forms, often
appearing in different cases of one and the same word as well. Your
point is well taken.

Kveðja,
Konráð.